The present invention relates to a rake head for a raking implement which is especially well-suited for raking and smoothing loose, granular materials.
Sand trap rakes are used by golfers and greenskeepers to smooth out foot prints and signs of play in the sand of bunkers on a golf course. These rakes are usually made of wood or plastic, and are often left on the course in the vicinity of a bunker for use by all golfers. After prolonged exposure to the sun and to temperature extremes, the wooden rakes tend to come unglued and to deteriorate, and the plastic rakes become brittle. In addition, both types of rakes are subject to breaking as a result of being thrown, over-stressed, run over by golf carts or mowing machines, or otherwise abused.
An object of the present invention is to provide a rake head for a raking implement, suitable for use as a sand trap rake, which is extremely durable and weather resistant.
Another object of the present invention is to provide a rake head for a raking implement which is very light weight and easy to use.
Yet another object of the present invention is to provide a raking implement which incorporates new and improved safety features in its design.
These and other objects are attained in a raking implement which includes a rake head comprising a crosshead formed from a resilient, elastomeric material, a plurality of tines extending from the crosshead, and a stiffener for increasing the rigidity of the resilient crosshead along its transverse axis or width. The tines are integrally formed with the crosshead from the resilient, elastomeric material. In a preferred embodiment, the tines are evenly spaced along a common edge of the crosshead and at least a portion of each tine is generally circular in cross-section. The cross-sectional diameter and the length of the circular portion determine the degree of resilience of each tine. The preferred embodiment of the crosshead also includes a blade-shaped edge extending along the crosshead. The blade-shaped edge is integrally formed with the crosshead from the resilient, elastomeric material. The blade edge can be used for smoothing or moving large amounts of material to, for example, fill a hole. The blade-shaped edge is similar in design to a squeegee and can be used to clear water from puddles on the green, or in other areas, in the same manner in which a squeegee is used to scrap water from flat surfaces.
The resilient, elastomeric material may be a material such as neoprene, which is a synthetic rubber produced by the polymerization of a chlorine derivative of acetylene. However, preferred materials include polymers of ethylene and especially copolymers of ethylene and propylene. An especially preferred material is an EPDM rubber compound having a Durometer hardness of approximately 80 and a tensile rating of approximately 1500 PSI (pounds per square inch).
The stiffener for the crosshead is preferably embedded within the resilient material of the crosshead. In a preferred embodiment, the stiffener is an insert which is also made of an elastomeric material. The melting point of the elastomeric insert is selected to be above that of the resilient elastomeric material which forms the crosshead. In an especially preferred embodiment, the elastomeric insert is made of heat-stabilized nylon.
The raking implement of the present invention includes a handle and hardware for attaching the handle to the crosshead. The handle is preferably a hollow tube formed of a non-metallic material. Although a tubular handle formed from a light-weight metal (such as aluminum) can be used to practice the present invention, the use of a non-metal handle is preferred to provide the safety features discussed below. An especially preferred non-metallic material is fiberglass. Other types of resin or plastic handles may be used as well.
The hardware for attaching the handle to the crosshead preferably includes a socket which is integrally formed with the resilient crosshead. The socket is hollow and cylindrically shaped for insertion into a hollow end of the handle. A threaded bolt and a wedge nut are provided for expanding the socket against the inner wall surface of the handle. In an especially preferred embodiment, the socket extends from the crosshead at an angle .alpha., as measured in a counter-clockwise direction from a centerline of the tines, and at an angle .beta., as measured from a clockwise direction from the blade-shaped edge. Both .alpha. and .beta. are preferably greater than 90.degree. to provide for additional advantages, as discussed below.
The materials from which the rake and rake head are formed are resistant to heat, light, temperature extremes, moisture and other environmental conditions. The resilience of the crosshead and of the individual tines prevents breakage due to impact, over stressing and other forms of abuse. The embedded stiffener and the provision of a plurality of individual tines assures enough rigidity in the assembly to adequately rake and smooth sand and other granular materials. The light-weight construction allows for fine raking with little exertion on the part of the user.
The non-metal construction of the preferred embodiment of the rake is especially important relative to several safety features. First, the non-metal embodiment of the rake will not attract lightning (which is an all-too-common golf course hazard) to the body of the user. Second, the relatively blunt and resilient nature of the tines prevents injuries which might otherwise result from stepping or falling on the rake. Third, the non-metallic materials of the rake reduce damage to equipment and possible injury to personnel which might otherwise result from inadvertently running over the rake with grass cutting equipment, golf carts, or other vehicles. Furthermore, the handle socket extends from the crosshead, as noted above, at angles .alpha. and .beta. with respect to the resilient tines and the blade-shaped edge. When .alpha. and .beta. are both greater than 90.degree., this configuration prevents the handle of the rake from flying into the face of a person who inadvertently steps on the upturned tines of a rake which is lying on the ground. This results from the fact that when the tines are facing in an upward, vertical position, the blade-shaped edge is pointing downward and away from the handle. Thus, when the crosshead is stepped on, the blade-shaped edge tends to oppose movement of the handle.
It should be noted that, while the rake of the present invention is particularly well suited for use as a sand trap rake, there are other situations in which many of these advantages and improved features would be applicable as well. For example, the moving, raking and/or smoothing of bulk granular materials such as grain, styrofoam beads, etc., can be accomplished with the rake of the present invention.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of a preferred embodiment of the invention, when considered in conjunction with the accompanying drawings.